Urologists and other physicians are interested in learning when and under what conditions leakage from urethra first occurs during an investigation of the bladder and urethra. In the course of the investigation, liquid is forced into the bladder through a catheter, and the pressure and the amount of liquid (urine and water) is known. The patient is asked to assume a number of positions, and to make various exertions, such as muscular contraction and coughing. In the course of these events, liquid will at times and under certain circumstances leak past the catheter. The conditions under which this leakage just begins is of importance to the physician in his investigation of the bladder and urethra.
While leakage can be visually detected, the relationship of its exact time of occurrence with respect to other measured parameters during a urodynamic procedure is critical for the proper evaluation of the test data. It is an object of this invention to provide a simple and rugged sensor and related circuity which will inform the urologist of the event of leakage, and if desired will also record the relative time and conditions under which it occurred, all without immediate attention by the physician.
A sensor to detect and notify of leakage past the urethra is disclosed in Ketchum U.S. Pat. No. 5,862,804, which does in fact detect such leakage, relying on a difference between ambient (room) temperature and the temperature of the leaked liquid. This instant invention, by the same inventor, is intended to provide optional or less complex references and measurements for the same purposes.